It is known that some electronic watches are designed so that when the power source is exhausted, the user has the option of himself changing it or having it changed easily. In such watches there is often provided, in an external part of the watch, usually the back of the case, an opening facing the battery housing and this opening is fluid-tightly closed by a removable cover. However, production of the cover and fitting it during final assembly of the watch constitute additional manufacturing operations compared to watches where exchange of the battery requires removal of the back. It is consequently important to simplify these operations and rationalise them as far as possible.
The following publications describe several examples of watches provided with such a cover: GB 2 178 561, JP 54-104 370, JP 54-136 869, GB 2 057 167, DE 2 000 544 and CH 650 121. In each of these constructions, the cover is provided with an annular sealing joint or packing member (O-ring) which must exactly and carefully be placed in position each time the cover is closed. Also, the cost of such packing members is not negligible. In publication CH 613 072 it is proposed to secure the cover in fluid-tight manner by using a piece of adhesive tape.
None of these known systems enables mating and fitting of the cover to be automated efficiently and the present invention aims to remedy this drawback by improving production of electronic watches fitted with a removable cover for changing the battery.